<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <link href="https://cdn.bootcss.com/animate.css/3.5.2/animate.css" rel="stylesh">
</head>
<body>
    <p id="test" class="animate">hello world</p>
    <script>
    // onmouseover--鼠标移入
    // onmouseout--鼠标移除
    var test=document.getElementById
    </script>
</body>
</html>